PRACTICAL METHODS FOR CRITICAL LOAD DETERMINATION AND STABILITY EVALUATION OF STEEL STRUCTURES
The critical load of a column, compression member or structure, calculated from a linear elastic analysis of an idealized perfect structure, does not necessary correspond with the load at which instability of a real structure occurs. This calculated critical load does not provide sufficient information to determine when failure, due to instability of the structure as a whole, will occur. To obtain this information it is necessary to consider the initial geometrical imperfections, eccentricities of loading, and the entire nonlinear load deflection behavior of the structure. However, this process in determining the critical load is too cumbersome and time consuming to be used in practical engineering applications. With today's computer programs that allow for the analysis of complex structures in which they incorporate advanced analytical techniques such as step-by-step large deformation analysis, buckling analysis, progressive collapse analysis, etc., it is just a natural progression that many structures are now analyzed with these tools. The goal of this research is to propose a practical methodology for critical load determination and stability evaluation of structures that are difficult or impossible to analyze with conventional hand-calculation methods, (e.g. the compression cord of a truss pedestrian bridge or a wind girt). The proposed methodology relies on a computer software package that has the ability to perform a second-order analysis taking in consideration end-restraints, reduced flexural stiffness (due to residual stresses in steel or cracked sections in concrete) and initial geometrical imperfections. Further, and importantly, a testing scheme was developed to validate the results from the computer in order to verify the methodology as a practical approach.
Book contributor Auraria Library
Collection auraria; additional_collections